I have a Geforce 8800GT that was a part of my old setup. I had then replaced it with a Geforce 480. I was then running the Geforce 480 on the top PCI-E slot and the Geforce 8800 on the bottom slot. It was running fine for a while but then I started noticing like a burning or melting plastic smell coming from the computer. At first I had thought that it was the new power supply giving out but it turned out to be the Geforce 8800 that was getting heated up by the 480's heatsync. Eventually, the computer would keep crashing due to the 8800 overheating. I then pulled the 8800 out of my computer and have been running the 480 ever since. I had to do this not only due to the smell but the increasingly unstable 8800.
Now, I have reseated the heatsync on the 8800 and it seems to be fine. However the computer does not power on at all when the card is plugged into PCI-E power. The card can be in the PCI-E slot with no additional PCI-E power connected and the computer boots (but the card does not work obviously). As soon as one or both PCI-E power connectors are plugged into the card, the lights on the mobo flash for a fraction of a second when the power button is pressed and then the PSU goes back into stand-by. Subsequent attempts to press the power button do nothing until the capacitors in the PSU are cycled (power off for 30 seconds and then back on). Also, the same thing happens even if the card is not in the PCIE slot. So the card can be sitting outside of the PC and as soon as either or both PCI-E power connectors are connected to the card, the same problem occurs. It seems as though the PSU is entering a safety mode and preventing powerup.
Now I have inspected the card for damage to the power circuit. It all seems fine except for a small line (could be a crack??) in one of the transistors. I have a hard time believing however that this bad transistor would be detected by the PSU and block startup...
I'm just looking for opinions here on whether it's worth trying to replace the transistor on the card or if it's simply done for.
Power Supply does not power on when video card is plugged in. Not a wattage issue. Unrelated to the motherboard.
I am running a 1000W PSU. I want the 8800GT back in there to power two extra LCD displays.
Thanks and sorry for the long post.